[spacemanspif]

Some numbers might help too. For instance when I first signed on this site, someone mentioned that for my commute to work, slowing down to 60 from 65mph would extend my drive by about 1.5minutes lol. If most drive 20 miles to your work on the highway slowing down to 60 from 65 would only cost them 2minutes. Since most don't work right on the off ramp nor live right on the on ramp, chances are that they have to deal with lights and traffic where the 2 more minutes would be absorbed without notice. Also do the math on how much money they can save by increasing their average MPG by just 1 or 2. Don't kill them with math but add just a little to prove the ideas.